CTRL + BACKSPACE == BACKSPACE in showkey -a

[chatumao]

I am trying to get CTRL + BACKSPACE delete a whole word, but the output from showkey -a shows that the terminal does not actually distinguish the two, both give me ^?.
I had a look at #56, but I'm unsure what the issue with that was. It does seem related, though.
The issue came up in PyCharm 2024.1.2 on Manjaro with Linux version 6.6.32-1-MANJARO. The shell used was zsh.
Can anyone reproduce on their system?